Ellipsograph instrument



May 11, 1954 s. FRIEDMAN 2,677,890 ELLIPSOGRAPH INSTRUMENT Filed March 29, 1952 iii ll 10 33 28 2g 33 O) M 12 31 9 51 x as q 8 37 24 3 41 11 33 Y Y Q as IN VEN TOR.

e e-I A Patented May 11, 1954 UNITED STATES PAT-NT OFFICE 2,677,890 ELLIPSOGRAPH INSTRUMENT Sifton Friedman, Lynbrook, N. Y.

Application March 29, 1952, Serial No. 279,283

4 Claims. 1

location and relative arrangement of parts, as described in detail hereinafter, as shown in the accompanying drawings and as finally pointed out in the appended claims.

In the accompanying drawings:

Figure 1 is a perspective view of an ellipsograph embodying the present invention; and

Figure 2 is a diagram illustrating the operation of the apparatus shown in Figure 1.

Now referring particularly to the drawing, it will be seen that the ellipsograph of the present invention essentially comprises a standard It, a beam II extending outwardly therefrom, driven and guiding assemblies each carried by the beam I I and gear means operatively connecting the driven assembly with the standard Ill.

The standard it is in the form .of an elongated upright member having around transverse cross section and having a base including downwardly diverging parts Iii-I2 and a horizontal part I3 joining the lower extremities of parts I 2l 2. The part I3 is apertured to slidably receive a set of three centering pins M which are disposed thereby in parallel spaced relation to one another and in a common plane, the intermediate pin I 4 being coaxially related to the standard H1. The pins M are adjustably secured in working position by thumb screws IS- which are received by tapped openings in the part It and which are horizontally disposed thereby for engagement with pins i i.

The beam I i which extends outwardly from the standard it is an elongated member, preferably formed of sheet material having a transverse cross section in the form of a channel provided with a vertically disposed main body portion I! and upper and lower horizontally disposed parallel flanges I8-I8. It will be understood, however, that the beam I I may be of any suitable form other than that shown. For securing the inner end of beam II to the standard Ill, the former is suitably provided witha laterally extending bracket in the form of a U-shaped member having a vertically disposed main body part I9 and upper and lower horizontally disposed parallel arms 2I-2I. The bracket is suitably rigidly secured by one edge of its body part l9 thereby in longitudinal continuation of the beam II with said body part I9 disposed in a, vertical plane normal to the web part I! and with the arms 2i-2I respectively "in coplanar relation to flanges I5-i8. The opposite end portions ofthe bracket are apertured to suitably receive vertically spaced portions of standard Ill for rotation of the bracket and the beam l I thereabout as a unit. The upper longitudinal edge of beam II is suitably graduated as at 20 for a purpose to be described hereinafter.

The driven and guiding assemblies which are carried by the beam II include slidable brackets 22 and 23 which are respectively provided with upper and lower horizontally disposed parallel flanges 2 i-24 and 26-46. These brackets 2223 are arranged to embrace spaced portions of the beam I i and are mounted for shifting movement therealong, each being secured in predeterminedly selected operative position by a thumb screw 21 which is received by a tapped opening in the upper flange of the bracket for engagement with the upper flange I8 of the main beam II.

Secured respectively to the slidable brackets 2223 are a pair of members 28 and 29, said members being in turn respectively provided with upper and lower horizontally disposed parallel flanges 3I3I and 32-32. The members 28 and 29 are suitably rigidly secured back to back respectively to the slidable brackets 22 and 23 with the flanges 3 I3I and 32-42 extending frontally of the main body portion I9 of the beam II.

As clearly appears in Figure 1, opposed portions of the flanges 3i3l are apertured to rotatably receive a vertically extending shaft 33, the upper end portion of which mounts an upwardly presenting bevel gear 35 suitably fixed thereon and disposed just above the upper flange BI. Slidably mounted upon the lower end portion of the shaft 33 is a horizontally disposed arm 34 secured to the shaft in adjusted position by a pair of threaded nuts 36 and 3?. The arm 34 is in the form of a flat member having formed therein an 89 elongated slot 38 through which the lower end of shaft 33 is projected, the slotted arm being locked in adjusted position relatively to the shaft 33 byclamping action of the nuts 36-31. The forward end of the arm 34 is downwardly and rearwardly turned to provid a vertically offset flanged part 39 which is apertured in registry with an aperture in the main body portion of the arm for receiving vertically spaced portions of the shank 4| of a marking element in the form of a drawing pen 42, the latter being thus positioned in depending relation with respect to the arm 34 for oscillation freely about the axis of its shank 4|.

With respect to the slidable guide member 23, opposed portions of flanges 3232 are apertured to oscillatably receive a shaft 43 having a head 44 formed on the upper end thereof for engagement with the uppermost flange 32. The lower end portion of the shaft 43 is apertured for slidably receiving a rod 46 which is provided at one end thereof with an internally threaded ferrule 46 adapted to threadedly receive the shank of the thumb screw 41 of the drawing pen 42.

The gear means operatively connecting the driven assembly with the vertical post or standard ll] includes an upwardly presenting bevel gear 48 suitably secured to the post in axially fixed position thereon. Extending in parallel spaced relation to the beam H is a square shaft 49, the opposite ends of which are respectively journalled for rotation in coaxially alined openings formed respectively in the part 9 at one end of the beam H and in a flange at the opposite end of the beam disposed in parallel relation to the part !9. The inner end of shaft 49 projects through the part l9 and mounts a bevel gear 52 for mesh engagement with the bevel gear 49.

Splined to a portion of shaft 49 intermediate its end is a bevel gear 53 which meshes with the bevel gear 35, the gear 53 being thus not only rotatable with the shaft 49 upon rotation of the bevel gear 52, but also shiftable axially of said shaft into any adjusted position therealong. For securing the gear 53 in its adjusted position along the shaft 49, the slidable bracket 22 is offset, as at 54, and slotted, as at 55. The offset section 54 is formed by bending an intermediate portion of the body portion of the bracket 22 outwardly of its plane to provide a rearwardly presenting channel which straddles the shaft 49 and serves as a hand-hold for shifting the bracket 22 into adjusted position along the beam H upon which it is slidably mounted. The opposite marginal edges of the slot 56 respectively engage opposite ends of the bevel gear 53 splined to the shaft 49, from which it will be apparent that as the bracket 23 is shifted longitudinally along the beam II in any adjusted position thereon, the assembly which includes the interengaging bevel gears 53 and 35, the vertical shaft 33, the arm 34 and the drawing pen 42 is correspondingly shifted into adjusted position.

It will be noted that the carries the rod 43 is independently adjustable along the beam Ii, this latter adjustment being effected upon adjustment of the bracket 22 to properly locate the rod 43 relatively to the shaft 33 as will appear more fully hereinafter. If desired, suitable arrangement may be provided for automatically effecting simultaneous adjust ment of the brackets 22 and 23 along the beam ll so as to properly position them relatively to each for any adjusted position of the shaft 33 toward or away from the post or standard It.

bracket 23 which The standard it and all of the shafts 33, 43 and 49 are disposed in a common vertical plane, it being noted also that all of the bevel gears 35, 52 and 53 have the same number of teeth, which number is just half that of number of teeth on the gear 48, in consequence of which the shaft 33 makes two revolutions about its own axis for each complete revolution of the beam ll about the axis of the standard it.

In the operation of the ellipsograph of the present invention, the major and minor axes of the desired ellipse, designated respectively by the letters XX and Y-Y, are preliminarily laid out as desired by the operator. Then the ellipsograph is adjusted for use by shifting the bracket 22 along the beam II and securing it in a position wherein the distance between the intermediate centering pin M, i. e., the axis of the standard 19, and the axis of the shaft 33 is equal to one half the sum of the semi-axes of the ellipse to be drawn. With the shaft 33 thus ad justed, and with the beam H swung into position paralleling the horizontal part l3 of the standard it! at the same time that the arm 34 is rotated into position paralleling the beam so that the beam H, the arm 34 and the aforesaid part 13 are all parallel, horizontally extendin arm 34 is then secured in such radially adjusted position relatively to the axis of the shaft 33 that the distance between the intermediate centering pin l4 and the point of the scribing instrument 42 is equal to one-half the length of the major axis of the desired ellipse. In this last adjusted position of the arm 34, the point of the instrument 42 will be spaced from the shaft 33 a distance equal to half the difference between the semi-major and semi-minor axes. If desired, the beam ll may be provided with a suitably graduated scale as shown which may be employed in conjunction with a pre-selected edge of the bracket 22 as an index for locating the shaft 33 the proper distance from the center of the ellipse to be drawn.

The operator next positions the centering pins M on the major axis and further positions the intermediate centering pin l4 at the center of the ellipse. Then with the point of the instru ment 42 suitably engaged with the surface to be marked, the beam H is rotated completely around the standard 10 by steadying the latter with one hand and moving the former through the medium of the handle 58, whereupon the in strument 42 describes the desired ellipse.

For example, Figure 2 diagrammatically shows successive positions of the ellipsograph as an ellipse 59 is described thereby. When the beam H is turned clockwise, the shaft 33 is also moved clockwise therewith in a circular path about the center of the ellipse. Simultaneously, the arm 34 is rotated in opposite counter-clockwise direction about the axis of the shaft 33 at the rate of two revolutions of said shaft 33 for each revolution of the beam H about the standard [0, and in passing through the upper left quadrant from the position designated by the letter A, thence through the positions B and C, and finally into the position D, the arm 34 rotates about the axis of shaft 33, that is, from a position at A parallel ing the major axis X--X into a position at D paralleling the minor axis Y-Y, thus shifting angularly through an angle of for the initial quadrant of the ellipse described, in consequence of which the instrument 42 shifts from the extremity of the major axis, which is disposed outside of the circular path of the shaft 33, to the its associated arm 34 will rotate a half turn in counter-clockwise direction, the net result being a 90 degree counter-clockwise angular displacement of the arm for each quadrant of the ellipse described by the scribing instrument. The operation of the ellipsograph in each succeeding quadrant is similar, and, of course, the complete ellipse is drawn when the beam H is rotated one complete revolution in either direction about the standard I0 as its center.

It will be seen that whenever the rod 46 is dis of the blades of the drawing pen 42 are disposed in tangential relation to the ellipse. This predetermined relation is maintained even in the intermediate positions of the ellipsograph, such as those designated by the letters B and C, by so shifting the bracket 23 on the beam II and se curing it in position that the distance between of the arm 34 relative to the rod as changes. For accommodating this angular change the effective length of the rod 46 is automatically changed as beam 1 I may be employed to locate the bracket 23 in any predetermined adjusted position upon the beam, a preselected edge of the bracket 23 serving in such case as the locating index for the bracket.

a chisel-point pencil. In addition, while the flat sides of the scribing instrument have been shown and described as constantly disposed in tangential relation to the portion of the ellipse being drawn, it will be understood that by suitable shifting of the bracket 23 along the beam 9 i into a position other than that above described for constant tangential disposition of the instrument instrument may be caused to progressively assume different positions relative to the line of the ellipse being drawn to thereby provide special shading effects. Furthermore, while the drawing illustratively shows a drawing pen as disposed normal to the surface upon which the ellipse is 6 to be drawn, it will be understood that the arrangement may be such as to position the lower end portion of the scribing element, whatever its eled edges.

Still further, while an ellipse having a major axis equal to twice the length of that of the minor axis is shown in Figure 2, it will be evident that ing the true perpendlcular or the true tangent to the ellipse at any desired point thereof.

It should be obvious, therefore, that the present invention is susceptible to various changes tended to claim the invention broadly, as well as specifically, as indicated by the appended claims.

pended claims, the term marking element or scribing element, wherever employed is intended to include not only the ruling pen 42 as illustrated but any other instrument such as a cutting blade, a striping brush or the like depacity of the ellipsograph of the present invention.

What is claimed as new and useful is:

1. In an ellipsograph, a central centering element having an upright standard which is fixed swingin movement thereabout, first and second brackets each selectively positionable along said by the first bracket, a shaft parallel to said stand- 3. An ellipsograph as set forth in claim 1 whereard, means mounting said last-named shaft on in the flat scribing element is elongated and has the second bracket for free oscillation about the a longitudinal axis parallel to the central standlongitudinal axis of the shaft, and guiding means ard.

extending between said scribing element and said 5 4. An ellipsograph as set forth in claim 1, freely oscillatable shaft on said second bracket wherein the beam is provided with graduations and operative to oscillate said element about its forming a single scale extending longitudinally rotary axis to maintain its operative edge in thereof, and wherein the movement of both the constant tangential relation to the elliptical line brackets on said beam is measurable by readings of the ellipse as it is described by the ellipso- 10 on the scale. graph, the efieotive length of said guiding means being shorter than the distance between the sec- References Cited in the fi Of this p t t 0nd bracket, and the central standard and said UNITED STATES PATENTS guiding means being located entirely outside the elliptical area being described. 15 gg g R i? J g 2. An ellipsograph as set forth in claim 1 where- 1 623348 't 1927 in the guiding means constitutes a rod, wherein 1e er one face of the flat scribing element is disposed FOREIGN PATENTS outwardly with respect to the ellipse, wherein an end of the rod is rigidly fixed to said outwardly 20 figg g g l i g gi gzg facing face and wherein said rod slidably en- 481,553 Germany Aug 24 1929 gages the freely oscillatable shaft. 

